Staying interested in a match is a lot harder than many people think. Throughout my career, I've always had trouble in the early rounds of a tournament mainly because it was hard for me to psychologically get up until I got to the quarters or the semis. What happened a lot of times is that I would fall behind early, maybe even lose the first couple of sets in a five-set match and then begin to concentrate. Still it wasn't something I could control from the start.

The roughest thing I ever said to an umpire was, 'Are you sure?'

There's a lot of ingredients go into being a good tennis player.

I often surprise myself. You can't plan some shots that go in, not unless you're on marijuana, and the only grass I'm partial to is Wimbledon's.

When you have the opportunity, you strike.

The time your game is most vulnerable is when you're ahead; never let up.

The next point - that's all you must think about.